She altered our perception of the disabled and remapped the boundaries of sight and sense

Helen Keller was less than two years old when she came down with a fever. It struck dramatically and left her unconscious. The fever went just as suddenly. But she was blinded and, very soon after, deaf. As she grew up, she managed to learn to do tiny errands, but she also realized that she was missing something. "Sometimes," she later wrote, "I stood between two persons who were conversing and touched their lips. I could not understand, and was vexed. I moved my lips and gesticulated frantically without result. This made me so angry at times that I kicked and...